Vinegar is often considered a more natural way to disinfect and clean things in and around the home. But what about using vinegar to sterilize or disinfect water? Is it possible and how effective is it?
Vinegar cannot sterilize, disinfect or purify water. Vinegar is not registered as a disinfectant by the EPA and should only be used to help reduce the number and spread of some germs on surfaces or objects.
In this post, I’ll explain the difference between sterilization, disinfection and sanitization and how effective vinegar is at each one. I’ll also provide details on what specific bacteria, parasites and viruses vinegar CAN kill, how effective it is, and how long it takes.
For emergency water sterilization, I’ll give you some other options that are supported by the EPA.
Does Vinegar Disinfect Water?
It kind of makes sense you should be able to disinfect water with vinegar. After all, there is almost a cult following around the supposed natural cleaning powers of vinegar.
There is absolutely nothing wrong with using vinegar to clean things in and around your home – in fact it can work pretty well for laundry machines, toilets, dishwashers, or windows for example. Some people, like my sister, even put vinegar in their hair – weird! 😐
So, why not use vinegar to kill nasties in drinking water?
Vinegar cannot be used to sterilize or disinfectant water even though it can kill various germs on surfaces.
Even though vinegar is a cheap and easily accessible alternative to commercial water sterilizers such as bleach or chlorine, you cannot trust vinegar to sterilize or disinfect water even in an emergency.
And here’s why…
The process of decontaminating water (or objects) falls under three categories. Each type of decontamination process refers to what they can and cannot kill:
- Sterilization = ALL microorganisms are killed, including spores.
- Disinfection = Elimination or reduction of SOME germs.
- Sanitization = RECUCTION in the number of germs.
Vinegar As A Water Sterilizer
Vinegar is not recommended as a water sterilizer by The Environmental Protection Agency (EPA) – even for emergency drinking water.
Vinegar will not kill ALL microorganisms on objects or surfaces, let alone in water. So, vinegar cannot be used as an effective water sterilizer.
Vinegar As A Water Disinfectant
Vinegar is not registered or certified by the EPA as a disinfectant. This is for good reason. For a product to meet the EPA’s strict criteria as a disinfectant it must be able to kill 99.999 % of germs on surfaces or objects within 10 minutes.
Vinegar will quickly kill some types of bacteria. However, other germs, including certain bacteria, viruses, and parasites can take longer than 10 minutes to kill. This makes vinegar unable to be classified as a disinfectant.
For example, the common flu virus, influenza A/H1N1, can be killed using 10 % malt vinegar – but this takes up to 60 minutes to occur (Greatorex et al., 2010).
Other bacteria are more resistant to lower vinegar concentrations and some bacteria may not be affected by low vinegar concentrations at all.
If you think about it, household vinegar is approximately 5 % acetic acid and 95 % water, so by adding it to more water you are basically diluting it down further. A highly diluted vinegar solution is unlikely to be effective at disinfecting water.
Vinegar As A Water Sanitizer
Vinegar can be an effective sanitizer against some bacteria and viruses on surfaces.
However, it’s important to note that no studies have been conducted that suggest vinegar can kill bacteria or viruses in water.
As mentioned above, vinegar is just acetic acid already diluted in water. By adding it to more water you are simply diluting it further and making it less and less effective.
However, here’s what we do know about what vinegar CAN kill – at least on surfaces anyway:
Can Vinegar Kill Bacteria?
Bacteria are small single-celled organisms, and there are tens of thousands of different known species.
Vinegar can effectively kill some types of bacteria. However, some bacteria species are more resistant to vinegar and require longer exposure times or higher vinegar concentrations to be effective.
White Vinegar Against Bacteria
An American study, published in the Journal of Infection Control and Hospital Epidemiology in 2000, tested how effective 5% Distilled White Vinegar (neat vinegar) was at killing a variety of common bacteria in a liquid solution, including:
- Staphylococcus aureus
- Salmonella choleraesuis (formerly Salmonella choleraesuis)
- Escherichia coli O157:H7 (AKA E. coli)
- Pseudomonas aeruginosa
- Enterococcus spp.
Distilled white vinegar effectively killed these bacteria after 5 minutes.
Distilled white vinegar was ineffective at killing these bacteria after a 30 second exposure.
In a similar study, published in the Journal of American Society For Microbiology in 2014, researchers found that 6 % white vinegar with a 30 minute exposure time could kill the bacteria that causes tuberculosis, Mycobacterium tuberculosis.
Other non-tuberculosis causing Mycobacterium, M. bolletii and M. massiliense, were more resistant to the 6 % vinegar. A 10 % vinegar and 30-minute exposure time was required to reduce their numbers.
Apple Cider Vinegar Against Bacteria
Apple cider vinegar can also kill some types of bacteria. A study published in Nature (2018) evaluated how well a 5 % apple cider vinegar inhibited bacterial growth in Petri dishes over a 24 h period.
This study showed the apple cider vinegar could kill the bacteria (listed below), but the concentration required did vary depending on species (see dilutions required in brackets).
- E. coli (Dilution: 1 part ACV to 50 parts water)
- S. aureus (Dilution: 1 part ACV to 25 parts water)
- C. albicans (Dilution: 1 part ACV to 2 parts water)
This study highlights that if you dilute your vinegar too much, you really can’t assume it will be effective at killing many different types of bacteria.
For example, based on the results from this study, you would need to mix about 1/3 apple cider vinegar to 2/3 water to be effective against c.albicans. This bacteria is commonly associated with yeast infections of the urinary tract, mouth, genitals and skin.
THAT’S A LOT OF VINEGAR!!!
As you can probably imagine, if you used this much vinegar to sterilize your drinking water, it will just end up tasting like vinegar!
What’s important here is none of these studies looked at how effective vinegar was at killing bacteria in containers of water.
In fact, I found no studies that looked directly at how effective vinegar was at killing things in water. This is probably because pure vinegar is not even that great at killing germs on surfaces, compared to commercial cleaners or even hot soapy water, let alone once it has been diluted by adding it to water.
How long does it take vinegar to kill bacteria?
To kill most bacteria, the exposure time to 5 % household white vinegar is approximately 30 minutes. Exposure times of less than 30 minutes or using vinegars with lower acidity may be ineffective at killing bacteria on surfaces.
To kill the common flu virus, influenza A/H1N1, a 60-minute exposure time and 10 % vinegar acidity is required.
Can Vinegar Kill Parasites?
Parasites are single-celled organisms commonly found in and around water.
Here are some examples:
Giardia (Giardia intestinalis)
Giardia are one of the most well known parasites, which can easily spread through water. Giardia are intestinal parasites that cause diarrhea and reduce food absorption.
A 2006 study showed vinegar could kill Giardia cysts. However, exposure time and the temperature changed how effective vinegar was against Giardia. For example, after a 30-minute exposure time to vinegar, just under 14 % of the Giardia cysts were killed at 40º F (4º C) and less than 17 % were killed at 75º F (24º C).
In fact, the best result was after a 3-hour exposure to vinegar at 75º F (24º C). And this only killed 47 % of the Giardia cysts. That’s NOT good!
Amoeba are single-celled organisms and are parasitic to humans. Some amoeba genus can infect and cause disease and even death in humans.
One of the more infamous are the parasitic brain-eating amoeba, Naegleria fowleri.
According to the CDC, you cannot get infected by drinking water that contains the brain-eating amoeba, N. fowleri. However, infections can occur if amoeba-contaminated water enters the nasal cavity.
No studies have investigated how effective or ineffective vinegar is at killing amoeba in water. However, as explained above, vinegar is basically terrible at killing Giardia cysts so I certainly wouldn’t trust vinegar to kill amoeba or amoeba cysts in water or on surfaces. I’d go for something a little stronger like bleach.
For a TON more information on amoeba check out this post I wrote: Filtering Amoeba From Water – Which Filters Can You Trust?
Can Vinegar Kill Viruses?
Vinegar and viruses are a bit more tricky!
The EPA does not review or recognize the effectiveness of common cleaning products such as vinegar against viruses.
There are some studies that show vinegar as effective against certain types of viruses.
A 2010 UK study showed the common flu virus (influenza A/H1N1) could be killed following a 60 minute exposure to 10% malt vinegar (4-8% acetic acid) diluted with water.
Importantly, when the malt vinegar was diluted down to just 1% with water, it was no more effective than hot water alone (Greatorex et al., 2010).
This kind of sounds promising, but it’s important to note that no study has shown vinegar as being more effective than commercial sterilizers and disinfectants at killing viruses.
Will Vinegar Kill Viruses In Your Laundry?
There is no current evidence that supports vinegar will kill viruses in your laundry. However, this does not mean it won’t – it just means no research has yet been carried out to provide an accurate enough answer.
Although adding vinegar to your laundry could theoretically kill of some germs such as a virus, vinegar is not even considered an effective virus disinfectant for dry objects or surfaces.
So, it won’t hurt to add vinegar to your laundry, but I wouldn’t rely on it to effectively kill any viruses.
If you still want to give it a try, as a rough guide you can add about a 1/2 cup of distilled white vinegar in your regular laundry compartment of your washing machine to help sanitize your clothes and machine. Remember that sanitize means it reduces the number of germs – not necessarily eliminating ALL germs. This includes viruses.
As a bonus you won’t have to add any laundry detergent if you don’t want to as the vinegar will also do a pretty good job at washing your clothes too.
What Is The Best Cleaning Vinegar?
Vinegar is solution of ethanoic (acetic) acid and water. Vinegar is what’s called a “weak acid”, meaning it does not completely disassociate (break apart) in water, although it is strong enough to kill some germs.
Household vinegars are typically around 5 % acetic acid to 95 % water. Vinegars over 6 % acidity are used for surface cleaning or even killing weeds.
The best vinegar for cleaning and germ reduction is distilled white vinegar or spirit vinegar that is >5% acidity. Cleaning vinegar should not contain any added colors to avoid staining surfaces.
The distillation process increases the vinegars acidity. Spirit vinegar also typically contains some alcohol, which aids in the killing of germs.
Cleaning with vinegars over 10% acidity will be more effective at killing germs, but will often require dilution with water and some level of personal protection such as gloves and eye protection.
Recommended Ways To Sterilize Water
The EPA recommends that in an emergency you can sterilize water using:
The EPA suggests that for water sterilization, the active ingredient in bleach should be 6% or 8.25% sodium hypochlorite. The household bleach should also be unscented, color safe, and with no added cleaners.
Use 1 part bleach to 100 parts water that you are treating.
Household iodine (or “tincture of iodine”)
Regular 2% tincture iodine will do (link to Amazon) – “tincture” just means it is dissolved in alcohol. This is the same sort of iodine you might already have in your medicine cabinet.
Use 5 drops of 2% tincture iodine per quart (1 liter) and wait for 30 minutes – use double the amount if the water is still cloudy.
Water disinfection (purification) tablets
Water purification tablets are made from either chlorine, chlorine dioxide, iodine or silver. All water purification tablets work well, but people usually pick one based on how long the tablets last or how it makes the water taste.
For much more information on water purification tablets and how long they last, check out this post I wrote.
High-test granular calcium hypochlorite (HTH)
Yes, this is what you use to shock a pool!
Finding true HTH can be tricky. On Amazon I would only recommend a few products. The products listed below have chlorine concentrations that are above 65 %, which is high enough to be classified as true HTH by the World Health Organisation (WHO):
- Ultima (73% Calcium Hypochlorite)
- POOLIFE Rapid Shock (68% calcium hypochlorite)
- DryTec (68% calcium hypochlorite)
Hint: if you are searching on Amazon, there is also an “HTH” brand of pool chlorine but their products do not have a high enough concentration to be classified as HTH.
First, make an HTH chlorine solution by stirring 1/4 ounce (1 tsp) of HTH into 2 gallons (7.6 L) water.
This doesn’t look or sound like much but don’t worry it’s plenty!
Second, you then add one part of your chlorine solution to 100 parts of water that you are treating.
Boiling is very effective at killing pathogenic bacteria, viruses and parasites (CDC 2020).
For cloudy water, first filter through cloth, paper towel or coffee filter. You can also wait for it to settle and decant the water off. Salt also acts as a flocculant (coagulant) and will help settle clay and silt particles in the water faster.
Store cooled water in a sanitized container and keep it well sealed.
WaterPurificationGuide has strict sourcing protocols and relies on peer-reviewed studies, medical associations, and academic research institutions. We avoid using tertiary references.
CDC 2020 Making Water Safe in an Emergency <https://www.cdc.gov/healthywater/emergency/making-water-safe.html>
Greatorex, J.S., Page, R.F., Curran, M.D., Digard, P., Enstone, J.E., Wreghitt, T., Powell, P.P., Sexton, D.W., Vivancos, R. and Nguyen-Van-Tam, J.S., 2010. Effectiveness of common household cleaning agents in reducing the viability of human influenza A/H1N1. PLoS One, 5(2), p.e8987. <https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0008987>
Rutala WA, Barbee SL, Aguiar NC, Sobsey MD, Weber DJ. Antimicrobial activity of home disinfectants and natural products against potential human pathogens. Infect Control Hosp Epidemiol. 2000 Jan;21(1):33-8. doi: 10.1086/501694. PMID: 10656352. <https://pubmed.ncbi.nlm.nih.gov/10656352/>
Yagnik, D., Serafin, V. and Shah, A.J., 2018. Antimicrobial activity of apple cider vinegar against Escherichia coli, Staphylococcus aureus and Candida albicans; downregulating cytokine and microbial protein expression. Scientific reports, 8(1), pp.1-12. <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5788933/>